The need for accurate and repeatable insertion of sterile needles, such as hypodermic, tuberculin or other needles, is a problem frequently encountered in many medical procedures. This accuracy is particularly necessary in performing tuberculin tests.
For many years, beginning in the early 1900's, an intradermal skin test had been used to detect the presence of tuberculin sensitivity in a test subject. This intradermal test, known as the "Mantoux Test," involved injecting a measured amount of proteins derived from the tubercle bacillus, the organism responsible fir tuberculosis, into the epidermis of the test subject. A positive test, indicated by swelling and redness at the injection site, provided evidence that the test subject had been exposed to the tubercle bacillus and established a presumptive diagnosis of clinical tuberculosis.
Although the intradermal Mantoux tuberculin test is highly reliable when correctly performed, it is difficult to administer accurately as it requires the insertion of the needle into the epidermis, the thin outer layer of the skin, and not into the dermis, the deep layer of skin. This necessitates inserting the needle at a very shallow angle, which is difficult to perform, even for the most skilled operators.
About twenty years ago a simplified tuberculin test, the "tine test", was developed. In this test, a small plastic button having multiple sharp tines projecting from the base of the button is used. The tines are coated with a dried tuberculin solution that, in theory, deposit a standard amount of tuberculin test material at a standard depth below the surface of the skin. Recently, the tine test has been proven to be inaccurate and infectious disease authorities are considering recommending that it be abandoned in favor of the original Mantoux tuberculin test. However, a whole generation of physicians and nurses are now unfamiliar with the test. Further, the accuracy required in administering the Mantoux Test makes it difficult to quickly and reliably perform, particularly by non-physicians.
Thus, there has been a considerable need for a device and method for reliably, repeatedly and quickly inserting a needle into the body of a person at a desired angle, direction and depth and, more particularly, for administering a Mantoux tuberculin test.